1. Patients must have histologically proven glioblastoma or gliosarcoma to be eligible for this protocol. Patients will be eligible if the original histology was low-grade glioma or anaplastic glioma (WHO II or III) and a subsequent histological diagnosis of glioblastoma or gliosarcoma is made. Only patients with histologically proven or imaging proven recurrent glioblastoma or gliosarcoma will be eligible for this protocol.